import React, {Component} from 'react';
import './index.css'
import {nanoid} from "nanoid";
import PropTypes from 'prop-types'

class Header extends Component {
    //对接收的props进行：类型、必要性的限制
    static propTypes = {
        addTodo:PropTypes.func.isRequired
    }
    //键盘事件的回调
    handleKeyUp = (event)=>{
        const {keyCode,target} = event
        if(keyCode !== 13) return
        console.log(target.value)
        if(target.value.trim() === ''){
            alert('输入不能为空')
            return;
        }
        //准备好一个todo对象
        const todoObj = {id:nanoid(),name:target.value,done:false}
        //将todoObj传递给App
        this.props.addTodo(todoObj)
        //清空输入
        target.value = ''

    }
    render() {
        return (
            <div className="todo-header">
                <input onKeyUp={this.handleKeyUp} type="text" placeholder="请输入你的任务名称，按回车键确认"/>
            </div>
        );
    }
}

export default Header;